Convertible bookcase



FIG. 1 is a front perspective view of a convertible bookcase showing thenew design;

FIG. 2 is a left side view, the right side view being a mirror thereof;

FIG. 3 is a front view, the rear view being a mirror thereof;

FIG. 4 is a top view; and,

FIG. 5 is a bottom view.

The broken lines shown in the drawings are for the purpose ofillustrating portions of the article and form no part of the claimeddesign.

The surface shading is intended to depict surface contour and forms nopart of the claimed design.

CLAIM The ornamental design for a convertible bookcase, as shown anddescribed.